-Max chain over 70 - 600
-Blue GUILT body did not appear - 900
-Completed with 230 left - 300
-No mistakes - 200
This is a very difficult operation if you're a renegade and don't use the Healing Touch. Once you realize the trick to it, though, it becomes much more reasonable.
Open up this son of a bitch and get inside. You'll see 5 normal lacerations. Suture 4 of them, and raise vitals to max, then suture the last one. Once you do get ready because you'll have to deal with wave after wave of Savatos. They will create a laceration, and then pour out from it to cause havoc. Now the hard part of this operation is that you MUST prevent the blue Savato from being formed. And the thing is, that if you don't incinerate the majority of Savatos in the first 0.5 seconds after they pour out of the laceration, they WILL form the blue Savato and that's goodbye XS rank.
If you think about it, 0.5 seconds isn't a lot. In fact, 0.5 seconds isn't that much more than an instant. Fortunately, there is a way: if you'll notice, the location where each laceration gets made is actually FIXED. It is not random. You know what this means. You will have to memorize where each laceration will appear so that you can have the pointer on it and ready to burn the Savato BEFORE they actually appear. The problem is that, unless you're some kind of legendary surgeon, it's impossible to have fast enough reflexes to take care of the Savato without knowing where they will come out prior.
Anyway, there will be 8 waves of Savato that you have to kill. The first laceration will appear on the center of the organ slightly to the right, and the Savato will pour towards the right. Use this knowledge and your laser to burn them immediately. Then very quickly suture the laceration.
The second laceration will appear on the right. Do the same things you did on the last one. The third laceration will appear at the bottom, then the fourth a bit above the center. The fifth will be slightly left of center.
The sixth one will appear very near to the fifth. Now, at this point, you will need to STOP suturing the lacerations. The Savato have been accelerating and from here on out there is simply no time. After the sixth wave, the 7th will appear slightly bottom-right of the center. Be quick in burning them. Now be very careful with the final wave. This one will come SO fast that I actually recommend you don't even let go of the button after burning the sixth one. Just keep the laser activated. This final wave will come out from dead center very near to the last one.
That'll be it. Suture the 3 lacerations. If the blue Savato wasn't formed, you will get the XS for sure. Unless, of course, you got a BAD somewhere. Don't let this happen.